The present invention relates to an apparatus for feeding a card with fiber material having a filling shaft which is fed by a preceding feed shaft. The fiber material is conveyed into the feed shaft via a conveying conduit by means of a stream of air.
It is known to provide a feed shaft in front of a filling shaft associated with a card and to supply the fiber material present in the feed shaft, by means of a conveying roller, to an opening roller which then delivers it to the filling shaft (DT-PS 1.202.193; Textilbertrieb, 1975, No. 8, page 96; Prospectus "Superkarde KU 12 mit Flockenspeisung FL 12" of Schubert & Salzer Maschinenfabrik AG). These known feed apparatus require two streams of air, one of which serves as a stream of conveying air for the fiber material to be fed into the feed shaft and the second stream of air, which is produced intermittently by means of a piston displaced in a cylinder or continuously by a blower, takes over the compression of the fiber material in the filling shaft. After passing through the appropriate shaft, the two streams of air emerge again from the shafts provided with outlets at the lower end. In order to prevent contamination of the free atmosphere by the streams of air leaving the shafts laden with dust, it is known to supply these two streams of air to the extraction installation of the card. It is a disadvantage of this solution, however, that the filters present in the card extractor are not sufficient for the additional cleansing of the two streams of air and it is, therefore, necessary to exchange these filters for ones having a greater capacity. This leads to increased constructional expense and is costly. A further disadvantage consists in the fact that air laden with dirt is drawn in from the spinning room to compress the fiber material present in the filling shaft, as a result of which both the air-conveying elements and also the fiber material in the filling shaft are contaminated.